The invention relates generally to measuring and controlling angles of rotation of a shaft and more particularly deals with detecting and/or controlling angular rotation of the shaft via detecting and/or measuring a commensurate linear displacement of a member along the shaft in response to the angular rotation.
The invention concerns improvements in controlling a rotational axis and particularly provides a means by which angular rotation of a device which is attached to the shaft may be monitored, measured, and/or controlled with a simplicity, reliability and efficiency of structure not found in the prior art.
A particularly unique feature of one embodiment of the invention provides for positional adjustment of each proximity switch, manually, by simply loosening a thumbknob, sliding the switch in a direction parallel to the rotational shaft, and retightening the thumbknob to lock that limit sensor in the readjusted position.
Another unique feature of the invention is the nonoverlapping linear output indication of angular rotations which may exceed three hundred sixty degrees in either or both of the clockwise and counterclockwise directions.
In another embodiment of the invention, a pointer is movable back and forth along the axis of rotation and relative to a linearly disposed scale which is observable by an operator of the device and which is calibrated to indicate and provide measurement of the degrees of angular rotation of the shaft.
In still another embodiment of the invention, the scale is replaced by the glass rod of a so-called linear glass encoder with the optical reader of the encoder being connected to the existing pointer for movement therewith.
In each of the embodiments, and variations thereof, it is preferred that the linearly movable member is engaged with and movable along the rotational shaft so as to provide a compact device which is relatively simple in construction and substantially protected from damage and which may be easily and manually readjusted.
Accordingly, it is an object of the invention to provide a relatively inexpensive, yet highly accurate monitor of the direction and amount of angular rotation of a rotational shaft for the purpose of measuring and/or controlling the rotation thereof.
Other objects and advantages of the invention will become more apparent from the following description in conjunction with the accompanying drawings.